Fbiedbich paul schmidt



F. P. SCHMIDT.

BLADE SHARPENER.

APPLICATION FILED AUG.9. 1920.

1,404,326, Patented Jan. 24,1922.

1 19.1. Fig.2. gun i "l f Il /ll UNITED STATES FRIEDRICH PAUL SCHMIDT, OF SUI-IL, THUBINGIA, GERMANY.

BLADE SHARPENER.

Specification of Letters Patent.

Patented Jan. 24:, 1922.

Application filed August 9, 1920. Serial No. 402,414.

T 0 all whom it may concern Be it known that I, Fnrnnnron PAUL SCHMIDT, a citizen of the German Republic, residing at 20 Herrenstrasse, Suhl, Thuringia, Germany, have invented certain new and useful Improvements in Blade Sharpeners, (for which I have filed an application in Germany, Aug. 7, 1919,) of which the following is a specification.

This invention relates to blade sharpeners in which the cutting edge of the blade is sharpened through pressure being applied to both of its sides by sharpening members between which the blade is inserted and which are caused to pass along the edge either by the blade or the sharpening men bers being moved. In distinction from known sharpeners of this general type, in which the sharpening members consist of ring-shaped protuberances on two rolls placed side by side, the sharpening members of my novel blade sharpener are made of windings of steel wire that are held by simple supports. By my improved construction the costs of the labor and material required in producing the sharpener are reduced, and the spring action of the steel wire sharpening members improves the effect of the sharpener.

constructional forms of the invention are illustrated in the drawing in which Fig. l is a plan View of a knife sharpener,

Fig. 2 being a front view, and

Fig. 3 a section of Fig. 1 on the line 3-3.

In Fig. 1 a is a base preferably of wood, 6 a sheet metal support for the sharpening members, this support being made of a single piece of sheet metal. 0 and d are the blade sharpening members which consist of steel wire of round cross section wound in the form of helices and screwed onto the bridge-pieces e, f of the support I), the diameter of the helices being such that each turn of the one helix enters into the space between two turns of the other. The support Z: is fixed on the base plate by a screw 9 at each end. A blade h, in position for sharpening, is shown in Fig. 2. B pressing the blade down between the helices and moving it at right angles to their coils the elastic helices will be caused to yield and moved apart and their pressure against the sides of the edge will produce a sharpenmg effect. The cross section of the steel wire used for the helices, instead of being round, may have some other suitable shape. Bllt it has been found that sharp-edged steel wire is not necessary, round wire being preferred on account of its cheapness.

By making the support for the helices of a single piece, an equal distance between the steel wires along the whole length of the helices is ensured, without any attention being paid in fixing the support on the base plate. This point is important in mass production. Another advantage obtained by this kind of support is that the pressure ex erted in sharpening a blade cannot cause the bridge-pieces to be forced apart.

An advantage of the arrangement shown in Fig. 1, in which the sharpening device is disposed at right angles to the length of the base at one end of the same, is that the apparatus is rendered easy to hold when used for sharpening and the danger of the blade slipping out and injuring the operator is eliminated. Besides, this form of the apparatus facilitates the packing of the same. The free space on the base at the side of the sharpening device is available for directions for using the apparatus, for advertisements, or for ornamentation by transfers, etc.

I claim:

1. A blade sharpener comprising two adj acent wire coils, a support for the said coils, and a holder for the said support.

2. A blade sharpener comprising two adjacent coils consisting of round steel wire, a support for the said coils, and a holder for the said support.

8. A blade sharpener comprising a base plate, two adjacent steel wire helices disposed at one end of the base plate at right angles to its length, a support for the said helices, and means for attaching the support to the said base plate.

In testimony whereof I have signed this specification in the presence of two witnesses.

F. PAUL SCHMIDT. Nitnesses I-lnwrc ALBRECHT, Lnoronn UNGER. 

